Adapter, extension, and connector assemblies for surgical devices

ABSTRACT

An adapter assembly for connecting an end effector to an electrosurgical instrument is provided. The adapter assembly includes a drive transfer assembly, first and second pusher assemblies, a drive member, an extension assembly, and a trocar assembly. The drive transfer assembly includes first, second and third rotatable shafts. Each pusher assembly is operably connected to a rotatable shaft for converting rotational motion from one rotatable shaft to longitudinal movement to perform a different function. The drive member is operably connected to the third rotatable shaft for transferring rotational motion from the third rotatable shaft to perform a third function. The extension assembly is operably connected to a distal end of the adapter assembly and includes at least one flexible band assembly operably connected to one of the first and second pusher assemblies. The trocar assembly is configured for releasable engagement with the extension assembly.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority to U.S. ProvisionalPatent Application No. 62/145,759 filed Apr. 10, 2015, the entiredisclosure of which is incorporated by reference herein.

BACKGROUND

1. Technical Field

The present disclosure relates generally to powered surgical devices.More specifically, the present disclosure relates to adapter andextension assemblies for selectively connecting end effectors to theactuation units of the powered surgical devices.

2. Background of Related Art

Powered devices for use in surgical procedures are known. To permitreuse of the handle assemblies of these powered surgical devices and sothat the handle assembly may be used with a variety of end effectors,adapter assemblies and extension assemblies have been developed forselective attachment to the handle assemblies and to a variety of endeffectors. Following use or following a useful life, the adapter and/orextension assemblies may be disposed of along with the end effector. Insome instances, the adapter assemblies and extension assemblies may besterilized for reuse.

SUMMARY

The present disclosure relates to an adapter assembly for connecting anend effector to an electrosurgical instrument. The adapter assemblyincludes a drive transfer assembly, first and second pusher assemblies,a drive member, an extension assembly, and a trocar assembly. The drivetransfer assembly includes first, second and third rotatable shafts.Each pusher assembly is operably connected to a rotatable shaft forconverting rotational motion from one rotatable shaft to longitudinalmovement to perform a different function. The drive member is operablyconnected to the third rotatable shaft for transferring rotationalmotion from the third rotatable shaft to perform a third function. Theextension assembly is operably connected to a distal end of the adapterassembly and includes at least one flexible band assembly operablyconnected to one of the first and second pusher assemblies. The trocarassembly is configured for releasable engagement with the extensionassembly.

In disclosed embodiments, the adapter assembly further comprises atleast one retention member, for example a first retention member and asecond retention member, configured to releasably couple the trocarassembly with the extension assembly. It is disclosed that eachretention member is configured to engage a flat portion of the trocarassembly, the first retention member is configured to engage the secondretention member, and that the second retention member is configured toengage the first retention member.

It is also disclosed that the retention member includes a nub configuredto releasably engage a respective detent of the trocar assembly.

Additionally, it is disclosed that the extension assembly defines alongitudinal axis, and that the retention member is movable in adirection perpendicular to the longitudinal axis through an opening ofthe extension assembly and into engagement with the trocar assembly.

The present disclosure also relates to an electromechanical circularstapling instrument including a handle assembly, an elongated portionextending distally from the handle assembly and defining a longitudinalaxis, a trocar assembly including a distal tip for penetrating tissue,and first and second retention members configured to releasably couplethe trocar assembly with the elongated portion. The trocar assembly isconfigured for releasable engagement with the elongated portion. Theretention members are configured to engage a flat portion of the trocarassembly. The first retention member is configured to engage the secondretention member, and the second retention member is configured toengage the first retention member. It is further disclosed that each ofthe first retention member and the second retention member is configuredto engage a flat portion of the trocar assembly.

In disclosed embodiments, the retention members include a nub configuredto releasably engage a respective detent of the trocar assembly.

It is also disclosed that the retention members are movable in adirection perpendicular to the longitudinal axis through an opening ofthe elongated portion and into engagement with the trocar assembly.

The present disclosure also relates to a method of securing a trocarassembly to an elongated portion of a surgical instrument. The methodincludes inserting a portion of a first retention member through a firstopening in an outer wall of the elongated portion of the surgicalinstrument, inserting a portion of a second retention member through asecond opening in the outer wall of the elongated portion of thesurgical instrument, engaging the portion of the first retention memberwith a first flat portion of the trocar assembly, engaging the portionof the second retention member with a second flat portion of the trocarassembly, and engaging the first retention member with the secondretention member.

In disclosed embodiments, the method also includes engaging a nub of thefirst retention member with a first detent of the trocar assembly andengaging a nub of the second retention member with a second detent ofthe trocar assembly.

It is further disclosed that engaging the first retention member withthe second retention member includes inserting an extension portion ofthe first retention member at least partially within a receptacle of thesecond retention member, and that the method also includes inserting anextension portion of the second retention member at least partially witha receptacle of the first retention member. It is also disclosed thatinserting the extension portion of the first retention member at leastpartially within the receptacle of the second retention member andinserting the extension portion of the second retention member at leastpartially with the receptacle of the first retention member occursimultaneously.

In disclosed embodiments, inserting the portion of the first retentionmember through the first opening in the outer wall of the elongatedportion of the surgical instrument includes moving the first retentionmember in a direction perpendicular to a longitudinal axis defined bythe elongated portion.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present disclosure are described herein withreference to the accompanying drawings, wherein:

FIG. 1 is a perspective separated view of an adapter assembly, inaccordance with an embodiment of the present disclosure, an extensionassembly, in accordance with an embodiment of the present disclosure,and an exemplary handheld electromechanical surgical device;

FIG. 2 is a perspective side view of the exemplary handheldelectromechanical surgical device of FIG. 1;

FIG. 3 is a perspective side view of the adapter assembly of FIG. 1;

FIG. 4 is a perspective side view of the adapter assembly of FIG. 3 withthe outer sleeve removed;

FIG. 5 is a perspective side view of the adapter assembly of FIGS. 3 and4 with proximal and distal housings of first and second pusherassemblies removed;

FIG. 6 is a cross-sectional side view of the adapter assembly of FIGS.2-4 taken along line 6-6 in FIG. 3;

FIG. 7 is a cross-sectional side view of the adapter assembly of FIGS.2-5 taken along line 7-7 in FIG. 5;

FIG. 8 is an enlarged, perspective view of a coupling assembly and atransfer assembly of the adapter assembly of FIGS. 2-7;

FIG. 9 is a perspective side view of the adapter assembly of FIGS. 2-7with the housing assemblies removed;

FIG. 10 is an enlarged view of the indicated area of detail of FIG. 9;

FIG. 11 is an enlarged view of the indicated area of detail of FIG. 6;

FIG. 12 is an enlarged view of the indicated area of detail of FIG. 7;

FIG. 13 is a perspective end view of the transfer assembly of FIG. 8;

FIG. 14 is an enlarged view of the indicated area of detail of FIG. 6;

FIG. 15 is an enlarged view of the indicated area of detail of FIG. 7;

FIG. 16 is an enlarged view of the indicated area of detail of FIG. 9;

FIG. 17 is a perspective side view of the extension assembly of FIG. 1;

FIG. 18 is a perspective side view of an inner flexible band assembly ofthe extension assembly of FIG. 17;

FIG. 19 is a perspective side view of an outer flexible band assembly ofthe extension assembly of FIG. 17;

FIG. 20 is a perspective side view of the inner and outer flexible bandassemblies of FIGS. 18 and 19 and an exploded view of a frame assemblyof the extension assembly of FIG. 17;

FIG. 21 is a perspective side view of the inner and outer flexible bandassemblies and the frame assembly of FIG. 20;

FIG. 22 is an enlarged view of the indicated area of detail of FIG. 21;

FIG. 23 is a front, perspective view of the inner and outer flexibleband assemblies and the frame assembly of FIG. 20;

FIG. 24 is an enlarged view of the indicated area of detail of FIG. 23;

FIG. 25 is a cross-sectional end view taken along line 25-25 of FIG. 17;

FIG. 26 is a cross-sectional end view taken along line 26-26 of FIG. 17;

FIG. 27 is an enlarged perspective side view of a distal end of theinner and outer flexible band assemblies and the frame assembly of FIG.20 including a proximal seal member and first and second distal sealmembers;

FIG. 28 is an exploded perspective view of the proximal seal member andfirst and second distal seal members of FIG. 27;

FIG. 29 is an exploded view of a trocar assembly of the extensionassembly of FIG. 17;

FIG. 30 is a perspective side view of the trocar assembly of FIG. 29;

FIG. 31 is a cross-sectional side view taken along line 31-31 of FIG.30;

FIG. 32 is a cross-sectional top view taken along line 32-32 of FIG. 17;

FIG. 33 is an enlarge cross-sectional view of the distal end of theextension assembly of FIG. 17;

FIG. 34 is a perspective side view of the adapter assembly of FIG. 3connected to the extension assembly of FIG. 17 and an end effector andan anvil assembly connected to the extension assembly;

FIG. 35 is an enlarged cross-sectional side view of the indicated areaof detail of FIG. 34;

FIG. 36 is a rear, perspective view of an adapter assembly according toanother embodiment of the present disclosure;

FIG. 37 is a perspective side view of the adapter assembly of FIG. 36with an outer sleeve and a handle member removed;

FIG. 38 is a perspective side view of the adapter assembly of FIG. 37with a base and a housing member removed;

FIG. 39 is a perspective side view of the adapter assembly of FIG. 38with a support structure removed;

FIG. 40 is a cross-sectional side view taken along line 40-40 of FIG.36;

FIG. 41 is a cross-sectional side view taken along line 41-41 of FIG.40;

FIG. 42 is a rear, perspective view of an adapter assembly according toyet another embodiment of the present disclosure;

FIG. 43 is a cross-sectional side view taken along line 43-43 of FIG.42;

FIG. 44 is a cross-sectional side view taken along line 44-44 of FIG.42;

FIG. 45 is a perspective view of a connector assembly according to anembodiment of the present disclosure;

FIG. 46 is an exploded perspective view of the connector assembly ofFIG. 45;

FIG. 47 is a perspective view of the connector assembly of FIG. 45 witha sleeve and first section of a tubular extension removed;

FIG. 48 is a perspective view of the connector assembly of FIG. 45 withthe sleeve removed;

FIG. 49 is a cross-sectional side view taken along line 49-49 of FIG.45;

FIG. 50 is a perspective view, with parts separated, of a distal end ofthe adapter assembly of FIG. 1 in accordance with embodiments of thepresent disclosure;

FIG. 51 is a transverse cross-sectional view of a portion of the distalend of the adapter assembly of FIG. 50;

FIG. 52 is a longitudinal cross-sectional view of the distal end of theadapter assembly taken along line 52-52 of FIG. 50;

FIGS. 53 and 54 are perspective views of a distal portion of the adapterassembly of FIG. 50, with some parts removed; and

FIG. 55 is a perspective view of a sensor assembly of the adapterassembly of FIG. 50.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the presently disclosed adapter assemblies and extensionassemblies for surgical devices and/or handle assemblies are describedin detail with reference to the drawings, in which like referencenumerals designate identical or corresponding elements in each of theseveral views. As used herein the term “distal” refers to that portionof the adapter assembly or surgical device, or component thereof,farther from the user, while the term “proximal” refers to that portionof the adapter assembly or surgical device, or component thereof, closerto the user.

With reference to FIG. 1, an adapter assembly in accordance with anembodiment of the present disclosure, shown generally as adapterassembly 100, and an extension assembly according to an embodiment ofthe present disclosure, shown generally as extension assembly 200, areconfigured for selective connection to a powered handheldelectromechanical instrument shown, generally as surgical device 10. Asillustrated in FIG. 1, surgical device 10 is configured for selectiveconnection with adapter assembly 100, and, in turn, adapter assembly 100is configured for selective connection with an extension assembly 200.Extension assembly 200 is configured for selective connection with atool assembly or end effector, e.g. tool assembly 30 (FIG. 34),including a loading unit, e.g. loading unit 40 (FIG. 34), and an anvilassembly, e.g., anvil assembly 50 (FIG. 34), for applying a circulararray of staples (not shown) to tissue (not shown).

As illustrated in FIGS. 1 and 2, surgical device 10 includes a handlehousing 12 having a lower housing portion 14, an intermediate housingportion 16 extending from and/or supported on lower housing portion 14,and an upper housing portion 18 extending from and/or supported onintermediate housing portion 16. A distal half-section of upper housingportion 18 defines a nose or connecting portion 18 a configured toaccept a corresponding drive coupling assembly 110 (FIG. 10) of adapterassembly 100. For a detailed description of the structure and functionof an exemplary electromechanical instrument, please refer to commonlyowned U.S. Pat. Appl. Publ. No. 2012/0253329 (“the '329 application”),the contents of which is incorporated by reference herein in itsentirety.

Adapter assembly 100 will now be described with reference to FIGS. 3-20.Referring initially to FIG. 3, adapter assembly 100 includes a proximalend 102 configured for operable connection to connecting portion 18 a(FIG. 1) of surgical device 10 (FIG. 1) and a distal end 104 configuredfor operable connection to extension assembly 200 (FIG. 1). Inaccordance with the present disclosure, adapter assembly 100 may besubstantially or fully rigid along the entire length.

Turning to FIGS. 3-5, from proximal end 102 to distal end 104 of adapterassembly 100, adapter assembly 100 includes a drive coupling assembly110, a drive transfer assembly 130 operably connected to drive couplingassembly 110, a first pusher assembly 160 operably connected to drivetransfer assembly 130, and a second pusher assembly 180 operablyconnected to drive transfer assembly 130. Each of drive transferassembly 130, first pusher assembly 160 and second pusher assembly 180are operably maintained within an outer sleeve 106 (FIG. 3). As will bedescribed in further detail below, a shaft 108 (FIG. 3) extendslongitudinally through adapter assembly 100 and is operably connected todrive transfer assembly 130.

With reference to FIGS. 5-9, drive coupling assembly 110 has acylindrical profile and is configured to selectively secure adapterassembly 100 to surgical device 10 (FIG. 1). Drive coupling assembly 110includes a connector housing 112 and a connector extension 114 fixedlyconnected to connector housing 112 by a mounting plate 113. Connectorhousing 112 and connector extension 114 operate to rotatably support afirst rotatable proximal drive shaft 116, a second rotatable proximaldrive shaft 118, and a third rotatable proximal drive shaft 120.Connector housing 112 and connector extension 114 of drive couplingassembly 110 also rotatably supports first, second, and third connectorsleeves 116, 118, and 120, respectively. Each of connector sleeves 122,124, 126 is configured to mate with respective first, second, and thirddrive connectors (not shown) of surgical device 10 (FIG. 1). Eachconnector sleeve 122, 124, 126 is further configured to mate with aproximal end 116 a, 118 a, 120 a of respective first, second and thirdproximal drive shafts 116, 118, 120.

Drive coupling assembly 110 also includes first, second and thirdbiasing members 122 a, 124 a and 126 a disposed distally of respectivefirst, second and third connector sleeves 122, 124, 126. Each of biasingmembers 122 a, 124 a and 126 a is disposed about respective first,second, and third rotatable proximal drive shafts 122, 124 and 126 tohelp maintain connector sleeves 122, 124, and 126 engaged with thedistal end of respective drive rotatable drive connectors (not shown) ofsurgical device 10 when adapter assembly 100 is connect to surgicaldevice 10. In particular, first, second and third biasing members 122 a,124 a and 126 a function to bias respective connector sleeves 122, 124and 126 in a proximal direction.

For a detailed description of an exemplary drive coupling assembly,please refer to the '329 application, the contents of which waspreviously incorporated by reference herein.

With reference to FIGS. 9-13, drive transfer assembly 130 (FIGS. 10 and13) of adapter assembly 100 has a cylindrical profile and operablyconnects distal ends of first, second and third rotatable proximal driveshafts 116, 118 and 120 to shaft 108, first pusher assembly 160, andsecond pusher assembly 180, respectively. Drive transfer assembly 130includes a support plate 132 (FIGS. 11 and 12) secured to a proximal endof connector housing 112 and a drive transfer housing 134 positionedadjacent support plate 132. Support plate 132 and housing 134 operate torotatably support a first rotatable distal drive shaft 136, a secondrotatable distal drive shaft 138 and a drive member 140.

First and second rotatable distal drive shafts 136 and 138 are eachoperably connected to respective first and second rotatable proximaldrive shafts 116 and 118 of drive coupling assembly 110 by a pair ofgears. In particular, distal ends of each of first and second rotatableproximal drive shaft 116 and 118 include a geared portion 142 a and 144a, respectively, which engages a proximal drive gear 142 b and 144 b ona proximal end of respective first and second distal drive shafts 136and 138. As shown, each of respective paired geared portion and proximaldrive gear 142 a, 142 b and 144 a, 144 b are the same size to provide a1:1 gear ratio between the respective rotatable proximal and distaldrive shafts. In this manner, respective rotatable proximal and distaldrive shafts rotate at the same speed. However, it is envisioned thateither or both of the paired geared portions and proximal drive gearsmay be of different sizes to alter the gear ratio between the rotatableproximal and distal drive shafts.

A distal end of third proximal drive shaft 120 of drive couplingassembly 110 includes a geared portion 146 a that engages a gearedportion 146 b formed on a proximal end of drive member 140 of drivetransfer assembly 130. The size of geared portion 146 a on thirdproximal drive shaft 120 and geared portion 146 b on drive member 140are the same size to provide a 1:1 gear ratio between third proximaldrive shaft 120 and drive member 140. In this manner, third proximaldrive shaft 120 and drive member 140 rotate at the same speed. However,it is envisioned that either or both of geared portions 146 a, 146 b maybe of different sizes to alter the gear ratio between third proximaldrive shaft 120 and drive member 140. A distal end of drive member 140defines a socket 145 that receives a proximal end 108 a of shaft 108.Alternatively, socket 145 may be configured to operably engage aproximal end 208 a of a drive shaft (FIG. 17) of an extension assembly200 (FIG. 17).

Drive transfer assembly 130 also includes a drive connector 148 (FIG.11) operably connecting first rotatable distal drive shaft 136 to firstpusher assembly 160 and a tubular connector 150 operably connectingsecond rotatable distal drive shaft 138 to second pusher assembly 180.In particular, a distal end of first rotatable distal drive shaft 136includes a geared portion 152 a that engages a geared portion 152 b ofdrive connector 148. A distal end of second rotatable distal drive shaft138 includes a geared portion 154 a that engages a drive gear 154 bsecured to a distal end of tubular connector 150.

As shown in FIG. 10, geared portion 152 a of first rotatable distaldrive shaft 136 is smaller than geared portion 152 b of drive connector148 to provide a gear ratio of greater than 1:1 between first rotatabledistal drive shaft 136 and drive connector 148. In this manner, driveconnector 148 rotates at a slower speed than first rotatable distaldrive shaft 136. Similarly, geared portion 154 a of second rotatabledistal drive shaft 138 is smaller than drive gear 154 b on tubularconnector 150 to provide a gear ratio of greater than 1:1 between secondrotatable distal drive shaft 138 and drive connector 148. In thismanner, tubular connector 150 rotates at a slower speed than secondrotatable distal drive shaft 138. However, it is envisioned that each ofpaired geared portion 152 a and geared portion 152 b, and geared portion154 a and drive gear 154 b may be the same size to provide a gear ratioof 1:1 between respective first rotatable distal drive shaft 136 anddrive connector 148 and between second rotatable distal drive shaft 138and tubular connector 150.

With particular reference to FIGS. 9-13, first pusher assembly 160includes proximal and distal housing sections 162, 164 (FIG. 11), aplanetary gear assembly 166 operably mounted within proximal housingsection 162, a screw member 168 (FIG. 11) operably connected toplanetary gear assembly 166 and rotatably supported within distalhousing section 164, and a pusher member 170 (FIG. 11) operablyconnected to screw member 168 and slidably disposed within distalhousing section 164. Planetary gear assembly 166 includes first andsecond planetary gear systems 166 a, 166 b (FIG. 10). First planetarygear system 166 a includes a central drive gear 172 a mounted on adistal end of drive connector 148 of drive transfer assembly 130 and aplurality of planetary gears 174 a rotatably mounted to a rotatablesupport ring 176.

Each planetary gear 174 a of first planetary gear system 166 a engagescentral drive gear 172 a and a toothed inner surface 165 of proximalhousing section 162. As central drive gear 172 a rotates in a firstdirection, i.e., clockwise, each planetary gear 174 a rotates in asecond direction, i.e., counter-clockwise. As each planetary gear 174 arotates in the second direction, engagement of planetary gears 174 awith toothed inner surface 165 of distal housing section 162 causesrotatable support ring 176 to rotate in the first direction. Conversely,rotation of central drive gear 172 a in the second direction causesrotation of each planetary gear 174 a in the first direction therebycausing rotation of rotatable support ring 176 in the second direction.The configuration of first planetary gear system 166 a provides areduction in the gear ratio. In this manner, the speed of rotation ofrotatable support ring 174 is less than the speed of rotation of centraldrive gear 170 a.

Second planetary gear system 166 b includes a central drive gear 172 bsecurely affixed to rotatable support ring 176 and a plurality ofplanetary gears 174 b rotatably mounted to a proximal end surface 168 aof screw member 168. Each planetary gear 174 b of second planetary gearsystem 166 b engages central drive gear 172 b and toothed inner surface165 of proximal housing section 162. As rotatable support ring 176 offirst planetary gear system 166 a rotates in the first direction therebycausing central drive gear 172 b to also rotate in the first direction,each planetary gear 174 b rotates in the second direction. As eachplanetary gear 174 b rotates in the second direction, engagement ofplanetary gears 174 b with toothed inner surface 165 of proximal housingsection 162 causes screw member 168 to rotate in the first direction.Conversely, rotation of central drive gear 172 b in the second directioncauses rotation of each planetary gear 174 b in the first direction,thereby causing screw member 168 to rotate in the second direction. Theconfiguration of second planetary gear system 166 b provides a reductionin the gear ratio. In this manner, the speed of rotation of screw member168 is less than the speed of rotation of central drive gear 172 b.First and second planetary gear systems 166 a, 166 b operate in unisonto provide a reduction in the gear ratio between first rotatableproximal drive shaft 116 and screw member 168. In this manner, thereduction in the speed of rotation of screw member 168 relative to driveconnector 148 is a product of the reduction provided by the first andsecond planetary gear systems 166 a, 166 b.

Screw member 168 is rotatably supported within proximal housing portion162 and includes a threaded distal end 168 b that operably engages athreaded inner surface 170 a of pusher member 170. As screw member 168is rotated in the first direction, engagement of threaded distal end 168b of screw member 168 with threaded inner surface 170 a of pusher member170 (which is keyed to permit axial translation and prevent rotationthereof) causes longitudinal advancement of pusher member 170, asindicated by arrows “A” in FIG. 12. Conversely, rotation of screw member168 in the second direction causes retraction of pusher member 170.

Pusher member 170 of first pusher assembly 160 of adapter assembly 100includes a pair of tabs 178 formed on a distal end thereof for engagingconnector extensions 240, 242 (FIG. 19) of outer flexible band assembly230 (FIG. 19) of extension assembly 200 (FIG. 17). Although shown astabs 178, it is envisioned that pusher member 170 may include anystructure suitable for selectively engaging connector extensions 240,242 of outer flexible band 230 of extension assembly 200.

With particular reference now to FIGS. 14-16, second pusher assembly 180is substantially similar to first pusher assembly 160, and includesproximal and distal housing sections 182, 184, a planetary gear assembly186 operably mounted within proximal housing section 182, a screw member188 operably connected to planetary gear assembly 186 and rotatablysupported within distal housing section 184, and a pusher member 190operably connected to screw member 188 and slidably disposed withindistal housing section 184. Planetary gear assembly 186 includes firstand second planetary gear systems 186 a, 186 b (FIG. 16). Firstplanetary gear system 186 a includes a central drive gear 192 a mountedon a distal end of tubular connector 150 of drive transfer assembly 130and a plurality of planetary gears 194 a rotatably mounted to arotatable support ring 196.

Each planetary gear 194 a of first planetary gear system 186 a engagescentral drive gear 192 a and a toothed inner surface 185 of proximalhousing section 182. As central drive gear 192 a rotates in a firstdirection, i.e., clockwise, each planetary gear 194 a rotates in asecond direction, i.e., counter-clockwise. As each planetary gear 194 arotates in the second direction, engagement of planetary gears 194 awith toothed inner surface 185 of distal housing section 182 causesrotatable support ring 196 to rotate in the first direction. Conversely,rotation of central drive gear 192 a in the second direction causesrotation of each planetary gear 194 a in the first direction therebycausing rotation of rotatable support ring 196 in the second direction.The configuration of first planetary gear system 186 a provides areduction in the gear ratio. In this manner, the speed of rotation ofrotatable support ring 194 is less than the speed of rotation of centraldrive gear 190 a.

Second planetary gear system 186 b includes a central drive gear 192 bsecurely affixed to rotatable support ring 196 and a plurality ofplanetary gears 194 b rotatably mounted to a proximal end surface 188 aof screw member 188. Each planetary gear 194 b of second planetary gearsystem 186 b engages central drive gear 192 b and toothed inner surface185 of proximal housing section 182. As rotatable support ring 196 offirst planetary gear system 186 a rotates in the first direction therebycausing central drive gear 192 b to also rotate in the first direction,each planetary gear 174 b rotates in the second direction. As eachplanetary gear 194 b rotates in the second direction, engagement ofplanetary gears 194 b with toothed inner surface 185 of proximal housingsection 182 causes screw member 188 to rotate in the first direction.Conversely, rotation of central drive gear 192 b in the second directioncauses rotation of each planetary gear 194 b in the first direction,thereby causing screw member 198 to rotate in the second direction. Theconfiguration of second planetary gear system 186 b provides a reductionin the gear ratio. In this manner, the speed of rotation of screw member188 is less than the speed of rotation of central drive gear 182 b.First and second planetary gear systems 186 a, 186 b operate in unisonto provide a reduction in the gear ratio between second rotatableproximal drive shaft 118 and screw member 188. In this manner, thereduction in the speed of rotation of screw member 188 relative totubular connector 150 is a product of the reduction provided by thefirst and second planetary gear systems 186 a, 186 b.

Screw member 188 is rotatably supported within proximal housing portion182 and includes a threaded distal end 188 b that operably engages athreaded inner surface 190 a of pusher member 190. As screw member 188is rotated in the first direction, engagement of threaded distal end 188b of screw member 188 with threaded inner surface 190 a of pusher member190 (which is keyed to permit axial translation and prevent rotationthereof) causes longitudinal advancement of pusher member 190.Conversely, rotation of screw member 188 in the second direction causesretraction of pusher member 190.

Pusher member 190 of second pusher assembly 180 of adapter assembly 100includes a pair of tabs 198 formed on a distal end thereof for engagingconnector extensions 220, 224 (FIG. 18) of inner flexible band assembly220 (FIG. 18) of extension assembly 200 (FIG. 17). Although shown astabs 198, it is envisioned that pusher member 190 may include anystructure suitable for selectively engaging connector extensions 240,242 of outer flexible band 230 of extension assembly 200.

Turning now to FIGS. 17-34, extension assembly 200 for operablyconnecting adapter assembly 100 (FIG. 3) with a circular loading unit,e.g. loading unit 40 (FIG. 34) and an anvil assembly, e.g., anvilassembly 50 (FIG. 34) will be described. In particular, a proximal end202 of extension assembly 200 operably connects with distal end 104(FIG. 3) of adapter assembly 100 (FIG. 3) and a distal end 204 ofextension assembly 200 operably connects with loading unit 40 and anvilassembly 50. As shown, extension assembly 200 provides a slightcurvature between proximal and distal end 202, 204. In an alternativeembodiment, extension assembly 200 may be straight or may include agreater curvature. In accordance with the present disclosure, extensionassembly 200 may be substantially or fully rigid along its entirelength.

Although extension assembly 200 will be shown and described as beingused to connect loading unit 40 and anvil assembly 50 to adapterassembly 100 (FIG. 3), it is envisioned that the aspects of the presentdisclosure may be modified for use with various loading units, anvilassemblies, and adapter assemblies. Exemplary loading units and anvilassemblies are described in commonly owned U.S. Pat. No. 8,590,763, andU.S. patent application Ser. Nos. 14/056,301 and 14/149,355, thecontents of each being incorporated herein by reference in theirentirety.

Extension assembly 200 includes an inner flexible band assembly 210(FIG. 18), about an outer flexible band assembly 230 (FIG. 19) slidablydisposed about inner flexible band assembly 210, a frame assembly 250(FIG. 20) for supporting inner and outer flexible band assemblies 210,230, a trocar assembly 270 (FIG. 28) operably received through inner andouter flexible band assemblies 210, 230, and a connector assembly 290for securing loading unit 40 (FIG. 34) to extension assembly 200. Anouter sleeve 206 (FIG. 17) is received about frame assembly 250 andtrocar assembly 270, and inner and outer flexible band assemblies 210,230 are slidealby received through outer sleeve 206. As will bedescribed in further detail below, extension assembly 200 may include adrive shaft 208 operably connected to trocar assembly 270 and extendingthrough proximal end 202 of extension assembly 200.

With reference to FIG. 18, inner flexible band assembly 210 includesfirst and second inner flexible bands 212, 214, a support ring 216, asupport base 218, and first and second connection extensions 220, 222.Proximal ends 212 a, 214 a of respective first and second inner flexiblebands 212, 214 are laterally spaced apart and securely attached tosupport ring 216. Distal ends 212 b, 214 b of first and second innerflexible bands 212, 214 are laterally spaced apart and securely attachedto a proximal end 218 a of support base 218. Each of first and secondinner flexible bands 212, 214 may be attached to support ring 216 and/orsupport base 218 in any suitable manner, including, for example, bypress-fitting, welding, adhesives, and/or with mechanical fasteners. Aswill be described in further detail below, inner flexible band assembly210 is configured to be slidably received about trocar assembly 270(FIG. 28) and within outer flexible band assembly 230 (FIG. 19) andouter sleeve 206 (FIG. 17).

First and second connection extensions 220, 222 of inner flexible bandassembly 210 extend proximally from support ring 216 and operablyconnect inner flexible band assembly 210 with pusher member 190 (FIG.15) of second pusher assembly 180 (FIG. 15) of adapter assembly 100(FIG. 3). In particular, each of first and second connection extensions220, 222 define respective openings 221, 223 configured to receive tabs198 (FIG. 15) of pusher member 190 (FIG. 15) of second pusher assembly180. Receipt of tabs 198 of pusher member 190 within openings 221, 223of respective first and second extensions 220, 222 secure inner flexibleband assembly 210 of extension assembly 200 with second pusher assembly180 of adapter assembly 100. First and second connection extensions 220,222 may be integrally formed with support ring 216, or attached theretoin any suitable manner.

Support base 218 extends distally from inner flexible bands 212, 214 andis configured to selectively connect extension assembly 200 with loadingunit 40 (FIG. 34). Specifically, a distal end 218 a of support base 218includes a flange 224 for operable engagement with an axially movableassembly (not shown) of loading unit 40 (FIG. 34). In one embodiment,flange 224 is configured for connection with a knife assembly (notshown) of loading unit 40 (FIG. 34).

With reference now to FIG. 19, outer flexible band assembly 230 issubstantially similar to inner flexible band assembly 210 and includesfirst and second flexible bands 232, 234 laterally spaced and connectedon proximal ends 232 a, 234 a to a support ring 236 and on distal ends234 b, 234 b to a proximal end 238 a of a support base 238. Each offirst and second outer flexible bands 232, 234 may be attached tosupport ring 236 and support base 238 in any suitable manner, including,for example, by press-fitting, welding, adhesives, and/or withmechanical fasteners. As will be described in further detail below,outer flexible band assembly 230 is configured to receive trocarassembly 270 (FIG. 28) therethrough.

First and second connection extensions 240, 242 of outer flexible bandassembly 230 extend proximally from support ring 236 and operablyconnect outer flexible band assembly 230 with pusher member 170 (FIG.12) of first pusher assembly 160 (FIG. 12) of adapter assembly 100 (FIG.1). In particular, each of first and second connection extensions 240,242 define respective openings 241, 243 configured to receive tabs 178(FIG. 12) of pusher member 170 of first pusher assembly 180. Receipt oftabs 178 of pusher member 170 within openings 241, 243 of respectivefirst and second extensions 240, 242 secures outer flexible bandassembly 230 of extension assembly 200 with first pusher assembly 180 ofadapter assembly 100. First and second connection extensions 240, 242may be integrally formed with support ring 236, or attached thereto inany suitable manner.

Support base 238 extends distally from outer flexible bands 232, 234 andis configured to selectively connect extension assembly 200 with loadingunit 40 (FIG. 34). Specifically, a distal end 238 b of support base 238includes a flange 244 for operable engagement with an axially movableassembly (not shown) of a loading unit (not shown). In one embodiment,flange 244 is configured for connection with a staple pusher assembly(not shown) of loading unit 40 (FIG. 34).

With reference now to FIGS. 20-26, frame assembly 250 includes first andsecond proximal spacer members 252, 254, and first and second distalspacer members 256, 258. When secured together, first and secondproximal spacer members 252, 254 define a pair of inner longitudinalslots 253 a for slidably receiving first and second flexible bands 212,214 (FIG. 18) of inner flexible band assembly 210 (FIG. 18) and a pairof outer longitudinal slots 253 b for slidably receiving first andsecond flexible bands 232, 234 (FIG. 19) of outer flexible band assembly230 (FIG. 19). First and second proximal spacer members 252, 254 furtherdefine a longitudinal passage 255 for receipt of trocar assembly 270.

In one embodiment, and as shown, first and second proximal spacermembers 252, 254 are formed of plastic and are secured together with asnap-fit arrangement. Alternatively, first and second proximal spacermembers 252, 254 may be formed of metal or other suitable material andmay be secured together in any suitable manner, including by welding,adhesives, and/or using mechanical fasteners.

First and second distal spacer members 256, 258 define a pair of innerslots 257 a for slidably receiving first and second flexible bands 212,214 (FIG. 18) of inner flexible band assembly 210 (FIG. 18) and a pairof outer slots 257 b for slidably receiving first and second flexiblebands 232, 234 (FIG. 19) of outer flexible band assembly 230 (FIG. 19).First and second distal spacer members 256, 258 further define alongitudinal passage 259 for receipt of trocar assembly 270.

In one embodiment, and as shown, each of first and second distal spacermembers 256, 258 are secured about inner and outer flexible bandassemblies 210, 230 and to outer sleeve 206 (FIG. 17) by a pair ofscrews 260 a, 260 b (FIG. 26). Alternatively, first and second distalspacer members 256, 258 may be secured together in any suitable manner,including by welding, adhesives, and/or using mechanical fasteners.First and second distal spacer members 256, 258 may be formed of metalor any other suitable material.

With reference now to FIGS. 27 and 28, frame assembly 250 furtherincludes a proximal seal member 262 and first and second distal sealmembers 264, 266. Each of proximal seal member 252 and first and seconddistal seal members 264, 266 include seals halves 262 a, 262 b, 264 a,264 b, 266 a, 266 b, respectively. Proximal seal member 262 is receivedbetween first and second proximal spacer members 252, 254 and first andsecond distal spacer members 256, 258. First half 264 a of first distalseal member 264 is secured to first half 266 a of second distal sealmember 266 and second half 264 b of first distal seal member 264 issecured to second half of second distal seal member 266. Proximal sealmember 262 and first and second distal seal members 264, 266 engageouter sleeve 206 (FIG. 17), inner and outer flexible bands 212, 214 and232, 234 of respective inner and outer flexible band assemblies 210, 230and trocar assembly 270 (FIG. 28) in a sealing manner. In this manner,proximal seal member 262 and first and second distal seal members 264,266 operate to provide a fluid tight seal between distal end 204 andproximal end 202 of extension assembly 200.

With reference to FIGS. 29-32, trocar assembly 270 of extension assembly200 includes an outer housing 272, a trocar member 274 slidably disposedwithin tubular outer housing 272, and a drive screw 276 operablyreceived within trocar member 274 for axially moving trocar member 274relative to tubular housing 272. In particular, trocar member 274includes a proximal end 274 a having an inner threaded portion 275 whichengages a threaded distal portion 276 b of drive screw 276. As drivescrew 276 is rotated within trocar member 274, engagement of innerthreaded portion 275 of trocar member 274 with threaded distal portion276 b of drive screw 276 causes longitudinal movement of trocar member274 within outer housing 272 of trocar assembly 270. Rotation of drivescrew 276 in a first direction causes longitudinal advancement of trocarmember 274 and rotation of drive screw 276 in a second direction causeslongitudinal retraction of trocar member 274. A distal end 274 b oftrocar member 274 is configured to selectively engage anvil assembly 50(FIG. 34).

A bearing assembly 278 is mounted to a proximal end 272 a of outerhousing 272 of trocar assembly 270 for rotatably supporting a proximalend 276 a of drive screw 276 relative to outer housing 272 and trocarmember 274. Bearing assembly 278 includes a housing 280, proximal anddistal spacers 282 a, 282 b, proximal and distal retention clips 284 a,284 b, proximal and distal bearings 286 a, 286 b, and a washer 288. Asshown, proximal end 276 a of drive screw 276 includes a flange 276 c forconnection with a link assembly 277. A distal portion 277 b of linkassembly 277 is pivotally received between first and second proximalspacer members 252, 254 and operably engages flange 276 c on drive screw276. A proximal end 277 a of link assembly 277 is configured foroperable engagement with a distal end 208 b of drive shaft 208.

With reference now to FIGS. 32 and 33, connector assembly 290 ofextension assembly 200 includes a tubular connector 292 attached to adistal end 206 a of outer sleeve 206 and about distal ends of inner andouter flexible assemblies 210, 230 (FIG. 26) and trocar assembly 270. Inparticular, a proximal end 292 a of tubular connector 292 is receivedwithin and securely attached to distal end 206 b of outer sleeve 206 bya retaining clip 294. An O-ring 296 forms a fluid tight seal betweentubular connector 292 of connector assembly 290 and outer sleeve 206. Adistal end 292 b of tubular connector 292 is configured to selectivelyengage a proximal end of loading unit 40 (FIG. 34). Distal end 292 b oftubular connector 292 engages the circular loading unit with a snap-fitarrangement, bayonet coupling, or in another suitable manner.

With reference now to FIGS. 34 and 35, extension assembly 200 isconnected to adapter assembly 100 by receiving proximal end 202 (FIG.17) of extension assembly 200 within distal end 104 of adapter assembly100. In particular, first and second connection extensions 220, 240,222, 242 of respective inner and outer flexible band assemblies 210, 230are received within sleeve 106 of adapter assembly 100 such that tabs178 of pusher member 170 of first pusher assembly 160 of adapterassembly 100 are received within openings 241, 243 of respective firstand second connection extensions 240, 242 of outer flexible bandassembly 230 to secure outer flexible band assembly 230 with firstpusher assembly 160 and tabs 198 of pusher member 190 of second pusherassembly 180 of adapter assembly 100 are received within openings 221,223 of first and second connection extensions 221, 223 of inner flexibleband assembly 210 to secure inner flexible band assembly 210 with secondpusher assembly 180.

As noted above, adapter assembly 100 may include a drive shaft 108 (FIG.3) that extends from distal end 104 of adapter assembly 100.Alternatively, extension assembly 200 may include a drive shaft 208extending from proximal portion 202 of extension assembly 200. In theevent both adapter assembly 100 includes drive shaft 108 and extensionassembly 200 includes drive shaft 208, prior to receipt of proximalportion 202 of extension assembly 200 within distal end 104 of extensionassembly 100, one of drive shaft 108, 208 must be removed fromrespective adapter assembly 100 and extension assembly 200. Duringreceipt of proximal portion 202 of extension assembly 200 within distalend 102 of adapter assembly 100, either distal end 108 b (FIG. 35) ofdrive shaft 108 b (FIG. 35) engages proximal portion 277 b (FIG. 35) oflink assembly 277, or proximal end 208 a (FIG. 17) of drive shaft 208(FIG. 17) is received within socket 145 of drive member 140 of drivetransfer assembly 130 of extension assembly 100 (FIG. 12).

After extension assembly 200 is operably engaged with adapter assembly100, and adapter assembly 100 is operably engaged with surgical device10 (FIG. 1), loading unit 40 (FIG. 34) of end effector 30 (FIG. 34) maybe attached to connector assembly 290 of extension assembly 200 and ananvil assembly 50 (FIG. 34) may be attached to distal end 274 b oftrocar 274 of extension assembly 200 in a conventional manner. Duringactuation of loading unit 40 and anvil assembly 50, longitudinaladvancement of pusher member 190 of second pusher assembly 180 ofadapter assembly 100, as described above, and as indicated by arrows “C”in FIG. 35, causes longitudinal advancement of outer flexible bandassembly 230 of extension assembly 200 and longitudinal advancement ofpusher member 170 of first pusher assembly 160, as described above, andas indicated by arrows “D” in FIG. 35, causes longitudinal advancementof inner flexible band assembly 210. Rotation of drive shaft 108 in afirst direction, as described above, and as indicated by arrow “E”,causes advancement of trocar 274 of extension assembly 200. Conversely,longitudinal retraction of pusher member 190 causes longitudinalretraction of outer flexible band assembly 230, longitudinal retractionof pusher member 170 causes longitudinal retraction of inner flexibleband assembly 210, and rotation of drive shaft 108 in a second directioncauses retraction of trocar 274 of extension assembly 200.

In one embodiment, inner flexible band assembly 210 is operablyconnected to a knife assembly (not show) of loading unit 40 (FIG. 34) ofend effector 30 (FIG. 34) attached to connection assembly 290 ofextension assembly 200, outer flexible band assembly 230 is operablyconnected to a staple driver assembly (not shown) of loading unit 40,and trocar 274 is operably connected to anvil assembly 50 (FIG. 34) ofend effector 30 (FIG. 34). In this manner, longitudinal movement ofinner flexible band assembly 210 causes longitudinal movement of theknife assembly, longitudinal movement of outer flexible band assembly230 causes longitudinal movement of the staple driver assembly, andlongitudinal movement of trocar 274 causes longitudinal movement ofanvil assembly 50 relative to loading unit 40.

With reference to FIGS. 36-41, an adapter assembly according to anotherembodiment of the present disclosure is shown as adapter assembly 300.Adapter assembly 300 is substantially similar to adapter assembly 100described hereinabove and will only be described as it relates to thedifferences therebetween.

As will become apparent from the following description, theconfiguration of adapter assembly 300 permits rotation of a distalportion 304 of adapter assembly 300 about a longitudinal axis “X” (FIG.37), relative to a proximal portion 302 of adapter assembly 300. In thismanner, an end effector, e.g. end effector 30 (FIG. 34) secured todistal portion 304 of adapter assembly 300 or an end effector secured toan extension assembly, e.g., extension assembly 200 (FIG. 17) which issecured to distal portion 304 of adapter assembly 300 is rotatable aboutlongitudinal axis “X” independent of movement of the surgical device(not shown) to which adapter assembly 300 is attached.

Adapter assembly 300 includes a base 306 and a support structure 308rotatable relative to base 306 along longitudinal axis “X” of adapterassembly 300. A rotation handle 310 is rotatably secured to base 306 andfixedly secured to a proximal end of support structure 308. Rotationhandle 310 permits longitudinal rotation of distal portion 304 ofadapter assembly 300 relative to proximal end 302 of adapter assembly300. As will be described in further detail below, a latch 312 ismounted to rotation handle 310 and selectively secures rotation handle310 in a fixed longitudinal position.

Proximal portion 302 of adapter assembly 300 includes a drive couplingassembly 320 and a drive transfer assembly 330 operably connected todrive coupling assembly 320. Distal portion 304 of adapter assembly 300includes a first pusher assembly 340 operably connected to drivetransfer assembly 330, and a second pusher assembly 350 operablyconnected to drive transfer assembly 330. Drive coupling assembly 320and drive transfer assembly 330 are mounted within base 306, and thus,remain rotationally fixed relative to the surgical device (not shown) towhich adapter assembly 300 is attached. First pusher assembly 340 andsecond pusher assembly 350 are mounted within support structure 308, andthus, are rotatable relative to the surgical device (not shown) to whichadapter assembly 300 is attached.

Drive coupling assembly 320 is configured to selectively secure adapterassembly 300 to a surgical device (not shown). For a detaileddescription of an exemplary surgical device and drive coupling assembly,please refer to commonly owned U.S. Provisional Patent Application Ser.No. 61/913,572, filed Dec. 9, 2013, the content of which is incorporatedby reference herein in its entirety.

Rotation knob 310 is rotatably secured to base 306. Latch 312 includes apin 312 a (FIG. 40) configured to lock rotation knob 310 relative tobase 306. In particular, pin 312 a of latch 312 is received within aslot 307 formed in base 306 and is biased distally by a spring 314 intoa notch 307 a (FIG. 40) formed in base 306 and in communication withslot 307 to lock rotation knob 310 relative to base 306. Proximalmovement of latch 312, as indicated by arrow “F” in FIG. 36, retractspin 312 a from within notch 307 a to permit rotation of rotation knob310 relative to base 306. Although not shown, it is envisioned that base306 may define a number of notches radially spaced about base 306 and incommunication with slot 307 that permit rotation knob 310 to be lockedin a number of longitudinal orientations relative to base 306.

Drive transfer assembly 330, first drive pusher assembly 340, and seconddrive pusher assembly 350 of adapter assembly 300 are substantiallyidentical to respective drive transfer assembly 130, first drive pusherassembly 160, and second drive pusher assembly 180 of adapter assembly100 described hereinabove, and therefore, will only be described asrelates to the differences therebetween.

Support structure 308 is fixedly received about first and second drivepusher assemblies 340, 350 and rotatably relative to base 306. As notedabove, rotation knob 310 is fixedly secured to the proximal end ofsupport structure 308 to facilitate rotation of support structure 308relative to base 306. Support structure 308 is retained with outersleeve 305 of adapter assembly 300 and is configured to maintain axialalignment of first and second drive pusher assemblies 340, 350. Supportstructure 308 may also reduce the cost of adapter assembly 300 whencompared to the cost of adapter assembly 100.

Support structure 308 respectively includes first, second, third,fourth, fifth, sixth, and seventh plates 360 a, 360 b, 360 c, 360 d, 360e, 360 f, 360 g, a first and a second plurality of tubular supports 362a, 362 b, first and second support rings 364 a, 364 b, a first and asecond plurality of ribs 366 a, 366 b, and a plurality of rivets 368.From proximal to distal, first and second plates 360 a, 360 b aremaintained in spaced apart relation to each other by the first pluralityof tubular supports 362 a, second and third plates 360 b, 360 c aremaintained in spaced apart relation to each other by first support ring364 a, third and fourth plates 360 c, 360 d are maintained in spacedapart relation to each other by the first plurality of support ribs 366a, fourth and fifth plates 360 d, 360 e are maintained in spaced apartrelation to each other by the second plurality of tubular supports 362b, fifth and sixth plates 360 e, 360 f are maintained in spaced apartrelation to each other by second support ring 364 b, and sixth andseventh plates 360 f, 360 g are maintained in spaced apart relation toeach other by the second plurality of support ribs 366 b. First, second,third, fourth, fifth, sixth, and seventh plates 360 a-g are heldtogether by a plurality of rivets 368 secured to first and seventhplates 360 a, 360 g and extending through second, third, fourth, fifth,and sixth plates 360 b-360 f, first and second support rings 364 a, 364b, and respective first and second plurality of tubular support 362 a,362 b.

Adapter assembly 300 operates in a substantially similar manner toadapter assembly 100 described hereinabove. In addition, as described indetail above, adapter assembly 300 is configured to permit rotation ofan end effector, e.g., end effector 30 (FIG. 34) attached to adapterassembly 300 or attached to an extension assembly that is attached toadapter assembly 300 to be selectively rotated about longitudinal axis“X” (FIG. 37) during use.

With reference now to FIGS. 42-44, an adapter assembly according toanother embodiment of the present disclosure is shown generally asadapter assembly 400. Adapter assembly 400 is substantially similar toadapter assemblies 100 and 300 described hereinabove, and therefore willonly be described as relates to the differences therebetween.

Adapter assembly 400 includes a proximal portion 402 and a distalportion 404 rotatable along a longitudinal axis “X” relative to proximalportion 402. Distal portion 404 includes a support structure 408 securedto outer sleeve 405 and formed about first and second pusher assemblies440, 450. Support structure 408 includes a plurality of reinforcingmembers 462 extending substantially the length of outer sleeve 405.Reinforcing members 462 each include a proximal tab 462 a and a distaltab 462 b which extend through outer sleeve 405 to secure reinforcingmember 462 within outer sleeve 405. Proximal tabs 462 of reinforcingmembers 462 are further configured to engage a rotation knob 410 ofadapter assembly 400. Adapter assembly 400 may include annular plates(not shown) positioned radially inward of reinforcing members 462 thatmaintain proximal and distal tabs 462 a, 462 b of reinforcing members462 in engagement with outer sleeve 405. The annular plates may alsoprovide structure support to distal portion 404 of adapter assembly 400.

With reference to FIGS. 45-49, a connection assembly according to anembodiment of the present disclosure is shown generally as connectionassembly 500. As shown and will be described, connection assembly 500 isconfigured to be attached to first and second tubular bodies (not shown)for connecting the first tubular body, i.e., adapter assembly 100 (FIG.3), 300 (FIG. 36), 400 (FIG. 42), to the second tubular body, i.e.,extension assembly 200 (FIG. 17). It is envisioned, however, that theaspects of the present disclosure may be incorporated directly into thefirst and second tubular bodies to permit connection of the firsttubular body directly to the second tubular body.

Connection assembly 500 includes a tubular base 510 and a tubularextension 520 formed of first and second sections 520 a, 520 b and anouter sleeve 522. As shown, tubular base 510 defines a pair of openings511 for securing tubular base 510 to a first tubular body (not shown).Alternatively, tubular base 510 may include only a single opening, oneor more tabs (not shown), and/or one or more slots (not shown), forsecuring tubular base 510 to the first tubular body (not shown). Aflange 512 extends from a first end of tubular base 510 and includes anannular rim 514 extending thereabout.

First and second sections 520 a, 520 b of tubular extension 520 aresubstantially similar to one another and each define an annular groove521 formed along an inner first surface thereof. Each of first andsecond section 520 a, 520 b of tubular extension 520 is configured to bereceived about flange 512 of tubular base 510 such that rim 514 oftubular base 510 is received within grooves 521 of first and secondsections 520 a, 520 b of tubular extension 520. Once first and secondsections 520 a, 520 b of tubular extension 520 are received about flange512 of tubular base 510, outer sleeve 522 of tubular extension 520 isreceived about first and second sections 520 a, 520 b of tubularextension 520 to secure tubular extension 520 to tubular base 510.

As shown, each of first and second sections 520 a, 520 b of tubularextension 520 define an opening 523 configured to be aligned with a pairof openings 525 in outer sleeve 522 to secure outer sleeve 522 to firstand second sections 520 a, 520 b. Either or both of first and secondsections 520 a, 520 b and outer sleeve 522 may include one or more tabs,and/or one or more slots for securing outer sleeve 522 about first andsecond extensions. Alternatively, outer sleeve 522 may be secured tofirst and second sections 520 a, 520 b in any suitable manner.

Outer sleeve 522 may be selectively secured about first and secondextensions for selective removal of outer sleeve 522 from about firstand second sections 520 a, 520 b to permit separation of tubularextension 520 from tubular base 510. Alternatively, outer sleeve 522 maybe permanently secured about first and second sections 520 a, 520 b toprevent tubular extension 520 from being separated from tubular base510. As noted above, although tubular base 510 and tubular extension 520are shown and described as forming an independent connection assembly500, it is envisioned that tubular base 510 may be formed on a firsttubular member, i.e., adapter assembly 100 (FIG. 3) and tubularextension 520 may be formed on a second tubular member, i.e., extensionassembly 200 (FIG. 17) such that the first tubular member may bedirectly connected to the second tubular member.

With reference to FIGS. 50-52, an alternate embodiment of a trocarassembly 1270 is shown in combination with an alternate embodiment of anextension assembly 1200. Trocar assembly 1270 is similar to trocarassembly 270 described above, and not all similarities will be discussedherein. However, while trocar assembly 270 is configured for secureengagement to link assembly 277 of extension assembly 200, trocarassembly 1270 is configured for releasable engagement with extensionassembly 1200.

With particular reference to FIG. 50, trocar assembly 1270 includes apair of flattened portions 1280 about its perimeter, and extensionassembly 1200 includes a pair of openings 1210 a, 1210 b through itsouter wall or sleeve 1206 (opening 1210 a is not visible in FIG. 50).When trocar assembly 1270 is engaged with extension assembly 1200,flattened portions 1280 of trocar assembly 1270 are axially aligned withopenings 1210 a, 1210 b of extension assembly 1200. In this position, apair of retention members 1300 a, 1300 b is insertable throughrespective openings 1210 a, 1210 b and adjacent (e.g., in contact with)flattened portions 1280.

More particularly, each retention member 1300 a, 1300 b includes anextension portion 1310 a, 1310 b and a receptacle 1320 a, 1320 b,respectively. Each extension portion 1310 a, 1310 b is configured toreleasably engage receptacle 1320 a, 1320 b of the opposite retentionmember 1300 a, 1300 b. That is, extension portion 1310 a of retentionmember 1300 a is configured to releasably engage receptacle 1320 b ofretention member 1300 b; extension portion 1310 b of retention member1300 b is configured to releasably engage receptacle 1320 a of retentionmember 1300 a. It is envisioned that extension portions 1310 a, 1310 brespectively engage receptacles 1320 b, 1320 a via a snap-fitconnection. It is further envisioned that retention member 1300 a isidentical to retention member 1300 b, which may be helpful to minimizemanufacturing costs and to facilitate assembly.

In use, to engage trocar assembly 1270 with extension assembly 1200,trocar assembly 1270 is inserted through a distal opening 1202 ofextension assembly 1200 until a proximal end 1276 a of a drive screw1276 of trocar assembly 1200 engages a link assembly of trocar assembly1200 (see link assembly 277 of trocar assembly 270 in FIG. 32, forexample). Next, extension portion 1310 a, 1310 b of each retentionmember 1300 a, 1300 b, respectively, is inserted through respectiveopening 1210 a, 1210 b of outer sleeve 1206, across flattened portion1280 of trocar assembly 1270 and into receptacle 1320 b, 1320 a of theother retention member 1300 b, 1300 a, respectively. That is, extensionportion 1310 a of retention member 1300 a is inserted through opening1210 a (or 1210 b) of outer sleeve 1206, across flattened portion 1280and into receptacle 1320 b of retention member 1300 b, and extensionportion 1310 b of retention member 1300 b is inserted through opening1210 b (or 1210 a) of outer sleeve 1206, across flattened portion 1280and into receptacle 1320 a of retention member 1300 a. The engagementbetween extension portion 1310 a, flattened portion 1280 and receptacle1320 b, and the engagement between extension portion 1310 b, flattenedportion 1280 and receptacle 1320 a is configured to prevent longitudinaltranslation of a trocar member 1274 of trocar assembly 1270 with respectto outer sleeve 1206 of trocar assembly 1200 (e.g., due to theengagement between extension portions 1310 a, 1310 b and walls 1282 offlattened portion 1280). Additionally, the engagement between extensionportion 1310 a, flattened portion 1280 and receptacle 1320 b, and theengagement between extension portion 1310 b, flattened portion 1280 andreceptacle 1320 a is configured to prevent relative rotation betweentrocar member 1274 of trocar assembly 1270 and outer sleeve 1206 oftrocar assembly 1200.

Additionally, and with particular reference to FIG. 50, each retentionmember 1300 a, 1300 b includes a nub 1302 (only nub 1302 associated withretention member 1300 a is shown), which is configured to mechanicallyengage a detent 1284 of trocar assembly 1270. It is envisioned that theengagement between nubs 1302 and detents 1284 helps maintain the properalignment and/or orientation between retention members 1300 a, 1300 band trocar assembly 1270.

To disengage retention members 1300 a, 1300 b from each other, it isenvisioned that a user can use a tool (e.g., a screwdriver-type tool) topush extension portions 1310 a, 1310 b out of receptacles 1320 b, 1320a, respectively. It is also envisioned that retention members 1300 a,1300 b are configured to be tool-lessly disengaged from each other andfrom trocar assembly 1270. Disengagement of retention members 1300 a,1300 b allows trocar assembly 1270 to be removed from outer sleeve 1206of trocar assembly 1200 (e.g., for replacement or cleaning). It isenvisioned that cleaning can occur by inserting a cleaning device atleast partially within at least one opening 1210 a, 1210 b of outersleeve 1206 of extension assembly 1200, and directing a cleaning fluid(e.g., saline) proximally and/or distally to help flush out anycontaminants that may be present within outer sleeve 1206, for example.

Additionally, while extension assembly 1200 and trocar assembly 1270 areshown used in connection with adapter assembly 100, the presentdisclosure also envisions the use of extension assembly 1200 and/ortrocar assembly 1270 with a surgical instrument (e.g., a circularstapling instrument) without the use of an adapter assembly.

With reference to FIGS. 53-55, the present disclosure also includes astrain gauge 1500, a position sensor 1520, and a memory sensor 1540(e.g., an E-PROM (erasable programmable read-only memory) sensor). Withparticular reference to FIG. 55, it is envisioned that a flexible cable1600 extends between strain gauge 1500, position sensor 1520, memorysensor 1540 and a printed circuit board (not shown), and from theprinted circuit board to an electrical connector disposed at proximalportion 302 of adapter assembly 300, for example.

It is envisioned that strain gauge 1500 is used to detect an axial loadexerted on the tissue during clamping of tissue. Here, it is envisionedthat if this load is too great, or exceeds a predetermined value, theuser (or stapling device 10 itself) may abort the stapling operation ormay choose to use a different stapling device 10 or adapter assembly100, for example.

It is envisioned that position sensor 1520 is used to detect the axialposition of the fasteners during the stapling process (e.g., when thefasteners are being ejected from adapter assembly 100). It is furtherenvisioned that memory sensor 1540 is configured to recognize the sizeand/or type of staple cartridge that is engaged with adapter assembly100 that is engaged with stapling device 10 and to relay thisinformation to handle housing 12 of stapling device 10.

Any of the components described herein may be fabricated from eithermetals, plastics, resins, composites or the like taking intoconsideration strength, durability, wearability, weight, resistance tocorrosion, ease of manufacturing, cost of manufacturing, and the like.

Persons skilled in the art will understand that the devices and methodsspecifically described herein and illustrated in the accompanyingdrawings are non-limiting exemplary embodiments. It is envisioned thatthe elements and features illustrated or described in connection withone exemplary embodiment may be combined with the elements and featuresof another without departing from the scope of the present disclosure.As well, one skilled in the art will appreciate further features andadvantages of the disclosure based on the above-described embodiments.Accordingly, the disclosure is not to be limited by what has beenparticularly shown and described, except as indicated by the appendedclaims.

1. An adapter assembly for operably connecting an end effector to anelectrosurgical instrument, the adapter assembly comprising: a drivetransfer assembly including first, second, and third rotatable shafts; afirst pusher assembly operably connected to the first rotatable shaftfor converting rotational motion from the first rotatable shaft tolongitudinal movement to perform a first function; a second pusherassembly operably connected to the second rotatable shaft for convertingrotational motion from the second rotatable shaft to longitudinalmovement to perform a second function; a drive member operably connectedto the third rotatable shaft for transferring rotational motion from thethird rotatable shaft to perform a third function; an extension assemblyoperably connected to a distal end of the adapter assembly, theextension assembly including at least one flexible band assemblyoperably connected to one of the first and second pusher assemblies; anda trocar assembly configured for releasable engagement with theextension assembly.
 2. The adapter assembly of claim 1, furthercomprising at least one retention member configured to releasably couplethe trocar assembly with the extension assembly.
 3. The adapter assemblyof claim 2, wherein the at least one retention member includes a firstretention member and a second retention member, wherein each of thefirst retention member and the second retention member is configured toengage a flat portion of the trocar assembly.
 4. The adapter assembly ofclaim 3, wherein the first retention member is configured to engage thesecond retention member.
 5. The adapter assembly of claim 4, wherein thesecond retention member is configured to engage the first retentionmember.
 6. The adapter assembly of claim 5, wherein each of the firstretention member and the second retention member is configured to engagea flat portion of the trocar assembly.
 7. The adapter assembly of claim2, wherein the at least one retention member includes a nub configuredto releasably engage a respective detent of the trocar assembly.
 8. Theadapter assembly of claim 2, wherein the extension assembly defines alongitudinal axis, and wherein the at least one retention member ismovable in a direction perpendicular to the longitudinal axis through anopening of the extension assembly and into engagement with the trocarassembly.
 9. An electromechanical circular stapling instrument,comprising: a handle assembly; an elongated portion extending distallyfrom the handle assembly and defining a longitudinal axis; a trocarassembly including a distal tip for penetrating tissue, the trocarassembly configured for releasable engagement with the elongatedportion; and a first retention member and a second retention memberconfigured to releasably couple the trocar assembly with the elongatedportion, each of the first retention member and the second retentionmember configured to engage a flat portion of the trocar assembly, andwherein the first retention member is configured to engage the secondretention member.
 10. The electromechanical circular stapling instrumentof claim 9, wherein the second retention member is configured to engagethe first retention member.
 11. The electromechanical circular staplinginstrument of claim 9, wherein each of the first retention member andthe second retention member includes a nub configured to releasablyengage a respective detent of the trocar assembly.
 12. Theelectromechanical circular stapling instrument of claim 9, wherein eachof the first retention member and the second retention member is movablein a direction perpendicular to the longitudinal axis through an openingof the elongated portion and into engagement with the trocar assembly.13. A method of securing a trocar assembly to an elongated portion of asurgical instrument, the method comprising: inserting a portion of afirst retention member through a first opening in an outer wall of theelongated portion of the surgical instrument; inserting a portion of asecond retention member through a second opening in the outer wall ofthe elongated portion of the surgical instrument; engaging the portionof the first retention member with a first flat portion of the trocarassembly; engaging the portion of the second retention member with asecond flat portion of the trocar assembly; and engaging the firstretention member with the second retention member.
 14. The method ofclaim 13, further comprising engaging a nub of the first retentionmember with a first detent of the trocar assembly.
 15. The method ofclaim 14, further comprising engaging a nub of the second retentionmember with a second detent of the trocar assembly.
 16. The method ofclaim 13, wherein engaging the first retention member with the secondretention member includes inserting an extension portion of the firstretention member at least partially within a receptacle of the secondretention member.
 17. The method of claim 16, further comprisinginserting an extension portion of the second retention member at leastpartially within a receptacle of the first retention member.
 18. Themethod of claim 17, wherein inserting the extension portion of the firstretention member at least partially within the receptacle of the secondretention member and inserting the extension portion of the secondretention member at least partially within the receptacle of the firstretention member occur simultaneously.
 19. The method of claim 13,wherein inserting the portion of the first retention member through thefirst opening in the outer wall of the elongated portion of the surgicalinstrument includes moving the first retention member in a directionperpendicular to a longitudinal axis defined by the elongated portion.